[Python-checkins] r64329 - peps/trunk/pep-0372.txt

[armin.ronacher]

Author: armin.ronacher
Date: Tue Jun 17 11:13:43 2008
New Revision: 64329

Log:
PEP 0372: added notice on comparing



Modified:
   peps/trunk/pep-0372.txt

Modified: peps/trunk/pep-0372.txt
==============================================================================
--- peps/trunk/pep-0372.txt	(original)
+++ peps/trunk/pep-0372.txt	Tue Jun 17 11:13:43 2008
@@ -118,7 +118,8 @@
     >>> d.byindex(2)
     ('foo', 'bar')
 
-    If there is no key for index an `IndexError` is raised.
+    If there is no key for index an `IndexError` is raised.  Slices are not
+    supported.
 
 ``odict.index(key)``
     Returns the index of a key.  If the key does not exist, a `ValueError` is
@@ -138,6 +139,17 @@
 ``odict.__reverse__()``
     Supports reverse iteration by key.
 
+``odict.__eq__()`` / ``odict.__ne__()``
+    Compares the odict to another object.  If it's compared to another
+    odict the ordering of items is taken into account, otherwise only
+    the keys and values.
+
+``odict.__cmp__()``
+    Ordered dicts are sorted by their items.  ``cmp(od1, od2)`` is
+    equivalent to ``cmp(od1.items(), od2.items())`` if both ``od1``
+    and ``od2`` are ordered dicts.  Otherwise the regular dict comparison
+    kicks in.
+
 
 Questions and Answers
 =====================
@@ -179,6 +191,20 @@
     >>> odict(l)
     collections.odict([('a', 42), ('x', 0), ('b', 23), ('c', 19)])
 
+Is the ordered dict a dict subclass?
+
+    Yes.  Like ``defaultdict``, ``odict`` subclasses ``dict``.
+
+Does ``odict.pop()`` support list-like popping of items?
+
+    No.  Neither ``odict.__getitem__()`` nor ``odict.pop()`` support
+    retrieving or deleting items by index.  Slices are not supported
+    either.  This would introduce ambiguities if integers or slice
+    objects are used as dict keys.
+
+    As a matter of fact, ``odict`` does not implement the ``Sequence``
+    interface.
+
 
 Example Implementation
 ======================